05-073.00 CH2M Hill: Valley Corridor Environmental StudiesTransportation tunprovement Board
UTIZZOV)Consultant Supplemental Agreement
Agency City of Spokane Valley Project Number 8 -3- 208(001) -1
Project Name City of Spokane Valley Corridor Project
Consulting Firm CH2M HILL, Inc.
Supplement Phase Design
Supplement Number 01
The Local Agency of City of Spokane Valley desires to supplement the agreement entered into with
CH2M HILL, Inc and executed on June 29, 2005. All provisions in the basic agreement remain in effect
except as expressly modified by this supplement.
The changes to the agreement are described as follows:
Section II, SCOPE OF WORK, is hereby amended as follows:
Task 1: Review Existing Model
PTV America, Inc. (PTV) will work with the City of Spokane Valley and CH2M HILL (CH2M) to provide
diagnostics of SRTC's baseline model and appropriateness for Valley Corridor analysis. PTV will follow a
protocol to ensure that the model is adequate for the task of evaluating corridor alternatives, specifically
assignments and network detail. The level of detail should be +/ -20 percent (PM peak hour) for arterial
links in the study area. Pertinent issues with trip generation and distribution should be identified. This
work is described next.
The existing 2003 SRTC model will be reviewed in the context of use for the City of Spokane Valley
forecasts, as follows:
• The review will include network coding (links, nodes, turns, volume -delay functions, impedances).
PDF plots of network attributes (such as Type, Number of Lanes, Speeds, Turn Penalties, and
Intersection Control) will be provided to the City for review of network inputs. Differences between
the model and actual conditions will be documented.
• Volume delay functions will be checked for appropriate use for both links and nodes, and
variations from expected practice will be documented. A PDF plot will be developed that shows
delays at the intersections, and link speed differences will be created to evaluate the impact of
these functions.
• Turn prohibitions and impedances will be checked for any that may be causing unexpected
routing in the model. These will be documented.
• Trip Generation and Distribution will be reviewed for any significant variations from typical
modeling practice. Differences will be documented.
• Traffic Assignment methodology will be reviewed and recommendations will be made. Particular
attention will be paid to those links where model volumes deviate +/- 20 percent.
Deliverable: Preparation of a memo that outlines items that can be improved to support the corridor study
as well as develops agency responsibility for those improvements. The documented differences will be
reviewed jointly by the City of Spokane Valley, SRTC, and CH2M.
Estimated Effort: 24 hours for Principal, including one on -site meeting; 8 hours for Engineer
Direct Cost: $300; Labor: $5,835; Total Estimate: $6,135
Schedule: Complete by September 6, 2005
OONSULTANT SUPPLEMENTAL AGREUDIT 02.000 PAGE 10F3
Tr an sport atio�� r iprovement Board
uf-26P Consultant Supplemental Agreement
Task 2: Update Base Model
After agreement by the City of Spokane Valley, SRTC, and CH2M on the changes to the base year
model, the changes will be made by PTV and work conducted as follows:
• The calibration will be tested in the City of Spokane Valley area to meet or exceed the standards
of 35 percent or less RMSE, R2 of 0.88 or greater, and 75 percent of all links classified as
Principal Arterials or higher within acceptable limits, as per figure A -3 in NCHRP 255.
• Arterial links in the Study Area will be within a +/- 20 percent deviation limit. Select Link plots will
be provided for up to three locations each on both Sprague Avenue and Appleway Blvd., for
review.
• Changes and the validation will be documented.
Estimated Effort: 8 hours for Principal; 24 hours for Engineer
No Direct Cost; Total Estimate: $3,800
Schedule: Complete by September 14, 2005
Task 3: Provide Forecasts
The Forecast 2025 base model will be updated with the calibration changes determined in Task 2, as
necessary, and after the model is updated, the following work will be done:
• Up to three network and/or land use alternatives will be coded and run.
PM forecasts will be provided for link volumes, as well as selected turn movement locations for
each of the forecasts.
• Selected Link PDF plots will be provided for up to three locations each on both Sprague Avenue
and Appleway Blvd.
Estimated Effort. 8 hours for Principal; 28 hours for Engineer
Schedule: Complete by September 21, 2005
No Direct Cost; Total Estimate: $4,150
Task 4: AM Analysis
AM base year counts for available locations in the study area will be added to the base year database.
Factors for the transposed PM matrices will be derived from NCHRP 365 and the recent Spokane and
Kootenai County Regional Travel Survey to test the AM assignment. These factors will be adjusted, as
necessary, to calibrate the AM assignment.
Forecasts will be provided for each of the four forecast scenarios using the matrix adjustment method. AM
forecasts will be provided for link volumes and selected turn movement locations for each of the
forecasts. Selected Link PDF plots will be provided for up to three locations each on both Sprague
Avenue and Appleway Blvd.
Estimated Effort: 12 hours for Principal; 36 hours for Engineer
No Direct Cost; Total Estimate: $5,700
Schedule: Complete by September 28, 2005
OONSULTANT SUPPLEMENTAL AGREEMENT 02000 PAGE20F3
Transportation Improvement Board
Consultant Supplemental Agreement
Task 5: Average Daily Traffic Analysis
Volume forecasts from the AM and PM analyses will be combined and factored to estimate the ADT for
each of the four forecast scenarios. Turning movements and selected link forecasts will not be provided.
Estimated Effort: 2 hours for Principal; 4 hours for Engineer
No Direct Cost; Total Estimate: $780
Schedule: Complete by September 28, 2005
Task 6: Optional Meetings
One meeting has already been included in Task 1. Additional meetings to discuss or present the model
findings or results will be billed at time and expenses at current PTV America, Inc. billing rates.
Section IV, TIME FOR BEGINNING AND COMPLETION, is amended to change the Completion Date
SUPPLEMENTAL COMPLETION DATE ' December 31, 2005
Section V, PAYMENT, shall be amended as follows as set forth in Exhibit A
MAXIMUM AMOUNT PAYABLE $184,762.69 (changed)
DOCUMENTS EXEMPT FROM PUBLIC DISCLOSURE
The section entitled "Exhibit A" contains confidential cost and rate data and is withheld from public disclosure
pursuant to 23 USC 112(2)(F).
Prenotification; confidentiality of data. A recipient of funds requesting or using the cost and rate data shall
notify any affected firm before such request or use. Such data shall be confidential and shall not be accessible or
provided, in whole or in part, to another firm or to any government agency which is not part of the group of
agencies sharing cost data under this paragraph, except by written permission of the audited firm. If prohibited by
law, such cost and rate data shall not be disclosed under any circumstances.
You may petition for a review of our findings pertaining to any redacted or withheld documents pursuant to
Spokane Valley Municipal Code (SVMC) 2.75.080; and obtain judicial review pursuant to RCW 42.56.550.
If you concur with this supplement and agree to the changes as stated above, please sign and date in the
appropriate spaces below.
Agency Signature
Date
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sulta t Signature
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CONSULTANT SUPPLEMENTAL AGREEMENT 02.DOC PAGE 3 O 3